JPH11321523A - Air bag device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air bag device capable of reducing a leak of pressure gas from between a cylinder unit housing an inflator and an air bag main unit mounted thereon. SOLUTION: In this air bag device 11, a bag unit inflating an air bag main unit 19 by pressure gas and a hold fabric 23 sewn on this bag unit to wrap a cylinder wall 21b of a diffuser 21 are provided, an opening 21a for jetting pressure gas is provided in the cylinder wall 21b, a pressure gas introducing port 26 communicating with the opening 21a is provided in the bag unit, connection fabrics 24, 24 are linked so as to be positioned outside the axial direction of the diffuser 21 in a connection part of the opening 21a with the pressure gas introducing port 26, between both side parts in the peripheral direction of the diffuser 21 in a part wrapping the cylinder wall 21b of the hold fabric 23, and these connection fabrics 24, 24 are sewn on the hold fabric 23 and the bag unit so as to enhance adhesion of the air bag main unit 19 relating to the diffuser 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag device mounted on a vehicle to reduce an impact on an occupant in a collision.

[0002]

2. Description of the Related Art Conventionally, as an airbag device, for example, those shown in FIGS. 11 and 12 are known. The airbag device includes an inflator 1 for ejecting a pressurized gas, a diffuser 2 having a built-in inflator 1 and ejecting a pressurized gas from an opening 2a.
An airbag body 3 that is inflated by the pressurized gas from the opening 2a.

The airbag body 3 includes a holding cloth 4 surrounding the cylindrical wall 2b of the diffuser 2, a contact cloth 5 having an opening 5a having the same shape as a pressure gas inlet 6, which will be described later, and an inflator 1.
A lower cloth 7 having a pressure gas inlet 6 into which a pressurized gas from is introduced, and an upper cloth 8 constituting a bag together with the address cloth 5 and the lower cloth 7.

The front and rear ends 4a and 4b of the holding cloth 4 are sewn before and after the opening 5a of the cloth 5 while loosening the central part 4c by a predetermined length, and the loosened central part 4c is pressurized. It is sewn to the lower cloth 7 so as to swell downward from the gas inlet 6. The upper cloth 8 is overlaid on the lower cloth 7 from above, and the peripheral edges thereof are sewn together.
Is formed.

The diffuser 2 is inserted into the insertion hole 9 formed by bulging the central portion 4c of the holding cloth 4 with the opening 2a facing upward. As a result, the opening 2a of the diffuser 2 communicates with the pressurized gas inlet 6 of the airbag body 3, and the cylindrical wall 2b of the diffuser 2 is wrapped by the holding cloth 4, so that the airbag body 3 is mounted and held on the diffuser 2. You.

[0006] In this airbag device, gas is not always inserted between the lower cloth 7 and the upper cloth 8 and both are folded and stored in an overlapping state. Gas is blown out and is sent between the two to inflate the bag body.

[0007]

By the way, in this conventional airbag apparatus, the diffuser 2 is only inserted through the insertion hole 9 formed by the holding cloth 4, so that the diffuser 2 in FIG. By being pulled in the direction of the arrow, a gap 10 is formed between both ends of the holding cloth 4, that is, between the diffuser 2 in the insertion hole 9 and the pressure gas inlet 6 of the lower cloth 7, and the pressure gas leaks from the gap 10. However, there is a possibility that the deployed shape of the airbag body 3 does not become a desired shape.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has been made in consideration of the above circumstances, and it is possible to reduce the leakage of pressurized gas from between a cylindrical body having a built-in inflator and an airbag body attached thereto. It is an object to provide a bag device.

[0009]

In order to solve the above-mentioned problems, the invention according to claim 1 is directed to an inflator for injecting a pressurized gas, a cylinder containing the inflator, and an airbag body attached to the cylinder. An opening for ejecting the pressurized gas to the outside of the cylinder is provided in a cylinder wall of the cylinder, and the airbag body is configured to include a bag inflated by the pressure gas and the bag body. A holding cloth for holding the bag cloth, and the cylindrical wall is attached to the holding cloth so that the bag body is held by the cylindrical body in a state where the opening communicates with the pressure gas inlet of the bag body. An airbag device in which both sides of the holding cloth wrapped around the cylindrical wall in the circumferential direction of the cylindrical body are sewn to the bag body, and between the two side parts of the holding cloth, Axial direction of the cylinder at the joint between the opening and the pressure gas inlet A connection member is stretched so as to be positioned outside of the airbag body, and the connection member is fixed to the holding cloth and the bag body so as to increase the adhesion of the airbag body to the cylinder. I have.

According to the first aspect of the present invention, the connecting member enhances the adhesion of the airbag body to the cylinder, that is, a gap is formed around the cylinder in cooperation with the holding cloth. It is fixed to the holding cloth and the bag body so as to be wrapped in a state where it does not exist, and furthermore, since this connecting member is located outside of the joint portion between the opening and the pressure gas introduction port in the axial direction of the cylindrical body, The flow of the pressurized gas going in the axial direction of the cylinder is hindered, and leakage of the pressurized gas from between the cylinder and the airbag body is reduced.

Further, since the connecting member is fixed to both the holding cloth and the bag, it also plays a role as a reinforcing material for increasing the joining portion between the holding cloth and the bag.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A specific embodiment of the present invention will be described with reference to FIGS.

The airbag device 11 is disposed so as to face an opening 13b formed in an upper surface 13a of an instrument panel 13 on a passenger seat side located below a windshield 12 of an automobile.

The airbag device 11 has a resin lid 14 held in the opening 13b. The airbag device 11 is a part of a vehicle body (not shown) (for example,
A module housing 17 is fixed to the steering support member via a bracket 15 and connected to the legs 14a of the lid 14 via coupling members 16, 16. Further, the airbag device 11
Includes an airbag body 19 folded and housed in an airbag body storage space 18 formed by the module housing 17 and the lid 14.

As shown in FIG. 2, an H-shaped cleavage groove 14b is formed on the rear surface of the lid 14, as viewed from above. Then, the cleavage groove 14b is cleaved by the pressing force when the airbag body 19 is inflated, and the leg portions 14a,
Cleavage groove 14b around hinge 14c near 14a
Are opened in the directions of the arrows A and A 'away from each other (spring opening), whereby a bulging opening is formed.

The module housing 17 has a cylindrical inflator 2 for ejecting a pressurized gas (for example, nitrogen gas).
0, and a cylindrical diffuser 21 for controlling the amount and direction of the pressurized gas ejected from the inflator 20 through the opening 21a. The diffuser 21 is fixed in the module housing 17 by fastening members 22, 22, and the airbag body 19 is attached and held by the diffuser 21.

As shown in FIGS. 3 and 4, the airbag body 19 has the same shape as a holding cloth 23 surrounding the cylindrical wall 21b of the diffuser 21, a connecting cloth 24 as a connecting member, and a pressure gas inlet 26 described later. And a lower cloth 27 having a pressurized gas inlet 26 through which the pressurized gas from the inflator 20 is introduced, an upper cloth 28 forming a bag together with the lower cloth 25 and the lower cloth 27. Is outlined.

A pair of connecting cloths 24, 24 are sewn to the holding cloth 23 so as to connect both ends of the slack portion while the central portion 23c is slackened by a predetermined length. The connecting cloth 24 is formed by bending a band-shaped cloth along its longitudinal direction to form a multilayer, and is formed in a vertical direction (arrow B in FIG. 3).
Direction), its thickness changes flexibly according to the external force applied to it. The entire peripheral length of the annular insertion hole peripheral portion 29 formed by the connecting cloth 24 and the central portion 23c is set to be equal to or slightly larger than the entire peripheral length of the outer surface of the cylindrical wall 21b of the diffuser 21 in a state where tension is not applied thereto. I have. In addition, a through hole 23d is formed in the central portion 23c of the holding cloth 23, and the above-mentioned fastening members 22, 22 are penetrated.

The front and rear ends 23a and 23b of the holding cloth 23 are
The sewing is sewn before and after the opening 25a of the patch cloth 25, and is sewn to the lower cloth 27 so that the central portion 23c swells from the pressure gas inlet 26. In addition, address cloth 2
Folding margins 25b, 25b are provided on the left and right of the opening 25a of the holding cloth 2 as shown in FIGS.
3. After the address cloth 25 and the lower cloth 27 are sewn once, the margins 25b, 25b are bent outward to enclose the connecting cloths 24, 24. 3 to 6, reference numeral 30 indicates a stitch of each of the above-described sewings.

An upper cloth 28 is overlaid on the lower cloth 27 and the peripheral edges thereof are sewn together to form a bag of the airbag 19 (see FIG. 10). The insertion hole 31 formed by bulging the central portion 23c of the holding cloth 23 below the lower cloth 27,
As shown in FIG. 7, the diffuser 21 is inserted with the opening 21a facing upward. The entire circumference of the insertion hole peripheral portion 29 corresponding to the left and right ends of the insertion hole 31 is, as described above, the cylindrical wall 21 of the diffuser 21 in a state where tension is not applied thereto.
b Since it is set to be equal to or slightly larger than the entire circumference of the outer surface, it is desirable that the diffuser 21 be inserted into the insertion hole 31 by attaching, for example, an illustrated insertion jig 32 to the distal end of the diffuser 21 in the insertion direction. .

The insertion jig 32 has a guide surface 32b whose diameter increases from the distal end portion 32a toward the diffuser 21 side. The vertical cross-sectional shape of the guide surface 32b has a curved shape that is convex toward the inside of the insertion jig 32. The insertion jig 32 gradually guides the diffuser 21 into the insertion hole 31 by gradually expanding the insertion hole peripheral portion 29 by the guide surface 32b, and after the insertion, the diffuser 21
Removed from

When the diffuser 21 is inserted through the insertion hole 31, the opening 21 a of the diffuser 21 is
The cylinder wall 21 b is wrapped around the holding cloth 23 while communicating with the pressurized gas introduction port 26 of No. 9. Moreover, the holding cloth 23 is sewn to both sides of the portion surrounding the cylindrical wall 21b,
Each connecting cloth 24, 24 spanned between its both sides
Are located axially outside the diffuser 21 at the joint between the opening 21a and the pressure gas inlet 26.
Each of the connecting cloths 24, 24 is provided with an insertion hole peripheral portion 29, 29, respectively.
, The diffuser 21 is wrapped around the diffuser 21 in a state in which no gap is formed around the diffuser 21 in cooperation with the holding cloth 23.

Next, the operation of this embodiment will be described.

In the airbag device 11, when an impact force of a predetermined value or more is applied to the vehicle body and the inflator 20 operates,
Pressurized gas is ejected from the inflator 20. The jetted pressure gas is sent into the bag of the airbag body 19 through the pressure gas inlet 26 while controlling the jet amount and jet direction through the opening 21 a of the diffuser 21.

When the folded bag is inflated by the pressurized gas, a part of the lid 14 is cleaved along the cleavage groove 14b to form a swelling opening, and from the swelling opening toward the occupant rearward of the vehicle body. Bulging towards. Thereby, the head and the like of the occupant on the passenger seat side are received by the airbag body 19, and the impact of the head and the like is reduced.

The airbag device 11 according to this embodiment
In this case, each of the connecting cloths 24, 24 is located on the outer side in the axial direction of the diffuser 21 at the joint between the opening 21a and the pressurized gas introduction port 26, and the connecting cloths 24, 24 are positioned with respect to the diffuser 21 of the airbag body 19. Since the diffuser 21 is sewn to the holding cloth 23 and the bag so as to wrap the diffuser 21 in a state where no gap is formed around the diffuser 21 in cooperation with the holding cloth 23, the airbag device is operated when the airbag device is operated. The flow of the pressurized gas going from the joint to the axial direction of the diffuser 21 is hindered, and the leak of the pressurized gas from between the diffuser 21 and the airbag body 19 is reduced.

That is, during operation of the airbag device, a force in the direction of arrow C (the direction in which the bag body expands) as shown in FIG. However, due to the connecting cloth 24 sewn to this portion and held in close contact with the cylindrical wall 21b of the diffuser 21, an arrow D against the force in the direction of arrow C is formed at a portion near the pressure gas inlet 26 thereof. In the direction of the arrow.
When it is set to be the same as the entire circumference of the outer surface of the cylindrical wall 21b, there is almost no gap between the diffuser 21 and the airbag body 19, and the leakage of the pressurized gas is reliably prevented.

In order to facilitate the insertion of the diffuser 21 into the insertion hole 31, the entire circumference of the insertion hole peripheral portion 29 is set to be slightly larger than the entire circumference of the outer surface of the cylindrical wall 21b of the diffuser 21. Before the operation of the airbag device, as shown in FIG.
Even when there is a slight gap 101 around the insertion hole peripheral portion 29 formed by the central portion 23c of the holding cloth 23 and the cylindrical wall 21b of the diffuser 21, when the airbag device is operated, the operation shown in FIG. ), The connecting cloth 24 is sewn and fixed to the holding cloth 23 at both ends, so that the airbag body 19 is inflated and deployed in the direction of arrow F (upward in the figure).
Receives the distributed load F, the distributed load F
Of the airbag body 1
When the distributed load F increases with the expansion and deployment of the
4 rotates around the torsion center CT point in the direction of arrow R in the figure, the point P on the inner edge side of the connection cloth 24 faces in the direction opposite to the direction of arrow F (downward in the figure), and the insertion hole The slight gap 101 between the peripheral portion 29 and the periphery of the cylindrical wall 21b of the diffuser 21 is closed, and leakage of the pressurized gas is reliably prevented.

In general, various reinforcing cloths other than those described above are provided in the airbag body in accordance with the inflation pressure, sewing strength and the like.
Is sewn to both the holding cloth 23 and the bag to function as a reinforcing material, so that the number and the thickness of the reinforcing cloth can be reduced as compared with the related art.

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to the above, and even if there is a design change or the like without departing from the gist of the present invention, the present invention will be described. Included in the invention. For example, in the above-described embodiment, the connecting cloth 24 is formed by bending a single band-shaped cloth, but as shown in FIG.
a are overlapped in the longitudinal direction and sewn together.
3 may be used instead of the connecting cloth 24. Alternatively, the connecting member may be configured using synthetic fibers or the like instead of the cloth.

[0031]

As described above, according to the first aspect of the present invention, the connecting member is used to increase the adhesion of the airbag body to the cylindrical body, that is, to separate the cylindrical body in cooperation with the holding cloth. The connecting member is fixed to the holding cloth and the bag so as to be wrapped around the pawl, and furthermore, since this connecting member is located outside the connecting portion between the opening and the pressure gas introduction port in the axial direction of the cylindrical body, the connecting portion is The flow of the pressurized gas going in the body axis direction is hindered, and the leakage of the pressurized gas from between the cylinder and the airbag body is reduced.

Further, since the connecting member is fixed to both the holding cloth and the bag, the connecting member also serves as a reinforcing material for increasing the joining portion between the holding cloth and the bag.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an airbag device according to an embodiment of the present invention.

FIG. 2 is a perspective view showing an instrument panel provided with the airbag device of FIG. 1;

FIG. 3 is a perspective view showing sewing of a connecting cloth to a holding cloth.

FIG. 4 is a perspective view showing sewing of each cloth constituting the airbag body.

FIG. 5 is a perspective view showing a state in which the cloths of FIG. 4 are sewn;

FIG. 6 is an explanatory diagram schematically showing a cross section taken along line EE in FIG. 5;

FIG. 7 is an explanatory view showing insertion of a diffuser into an airbag body.

FIG. 8 is an explanatory view showing a state of a force acting on a portion near a pressure gas introduction port of the airbag body when the device is operated.

9A is an explanatory diagram showing a state of a connecting cloth near a pressure gas introduction port before operation of the apparatus, and FIG. 9B is a view showing an operation state of a connection cloth near a pressure gas introduction port at the time of operation of the apparatus. FIG.

FIG. 10 is a perspective view showing another example of the connection cloth.

FIG. 11 is a perspective view showing a configuration of a conventional airbag device along a manufacturing process.

FIG. 12 is an explanatory view showing a state at the time of operation of a conventional airbag device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Airbag apparatus 19 Airbag main body 21 Diffuser (cylindrical body) 21a Opening 21b Cylindrical wall 23 Holding cloth 24 Connecting cloth (connecting member) 26 Pressure gas inlet

Claims (1)

[Claims] An inflator for injecting a pressurized gas, a tubular body containing the inflator, and an airbag body attached to the tubular body, wherein the pressurized gas is applied to a tubular wall of the tubular body. An opening for ejecting to the outside is provided, and the airbag body includes a bag body inflated by the pressurized gas and a holding cloth for holding the bag body in the cylindrical body. The cylindrical wall is wrapped by the holding cloth and the cylindrical circumferential direction of a portion wrapped around the cylindrical wall of the holding cloth so that the bag is held by the cylindrical body in a state of being in communication with the pressure gas introduction port. An airbag device in which both side portions of the airbag device are sewn to the bag body, between the both side portions of the holding cloth, in the axial direction of the cylindrical body at the joint between the opening and the pressure gas introduction port. A connecting member is bridged so as to be located outside, and the connecting member is An airbag device, wherein the airbag body is fixed to the holding cloth and the bag so as to enhance the adhesion of the airbag body to the cylinder.